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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Posted on 29 November 2016 by John Mason, BaerbelW

Dear Mr President-elect,

On 6 Nov 2012, at 11:15 am, you tweeted:

“The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive.”

We'd like to take you on a quick tour back through the ages, because the early understanding of Earth's climate - and the role that carbon has to play in it - came from the West, not the East. Let's run through it quickly.

In 1800, British astronomer William Herschel first measured the heat that occurs in the warm – now known as infra-red (IR) – part of the spectrum. In 1824, French engineer Jean Baptiste Joseph Fourier calculated that Earth should be colder than it is, at its orbital distance from the Sun. Today, it is common knowledge that outgoing IR radiation is emitted by the Earth's surface in response to heating by the Sun. But Fourier was the first to figure out that the IR was being slowed down during its journey back out to space. The air, he said, must act as a form of insulating blanket, keeping the planet warm. Smart guy.

This was just two years before Samuel Morey patented the first internal combustion engine.

In 1861, Anglo-Irish physicist John Tyndall observed that some atmospheric gases were transparent to IR radiation. But he found that others, like water vapor and carbon dioxide, were powerful IR absorbers. He was the first to propose that changes in the amount of carbon dioxide in the atmosphere could influence the Earth's climate. In 1896, Swedish scientist Svante Arrhenius took it further. He made the first detailed calculations to see what a doubling of carbon dioxide levels might do to temperatures. His answer was a 5-6°C increase in the average global temperature. His ‘hot-house theory’ was set out for the first time in 1908 in his popular book ‘Worlds in the Making’.

In 1909, American astronomer Andrew Douglass developed the techniques of studying tree-rings and was the first to find the connection between tree ring widths and climate. In 1931, American physicist E.O Hulburt ran calculations to determine the effect of doubling carbon dioxide with the added burden of water vapor. His figure? 4°C of warming. In 1938, English engineer Guy Callendar discovered evidence of a warming temperature trend in the early twentieth century. He also found that CO2 levels were increasing and he warned that over the coming centuries there could be a climate shift to a permanently warmer state.

Mr President-elect, you were born in June 1946, in the early years of the Cold War. It was a time that saw a surge in atmospheric research. The properties and behaviour of IR radiation came under even more scrutiny in the quest to develop heat-seeking missiles. By the 1950s, the advantage of computer-power, something we take for granted today, made it possible to dissect the atmosphere in ever-greater detail. 1956 - when you were just ten years of age - saw the publication of the landmark paper, 'The Carbon Dioxide Theory of Climatic Change', by Canadian-American physicist Gilbert Plass. The paper confirmed that more carbon dioxide would have a warming effect and that doubling levels of that gas would result in a warming of 3-4°C. The very title of the paper tells you that "climate change" is not a term made up in recent years for political reasons, as some try to claim.

Mr President-elect, we've known about this stuff for decades. None of the above is "politicized science". Even the youngest milestones along the climate science timeline above are now more than half a century old. Most of them are older than you. They were all attained through the hard work and dedication of our best American and European scientists. These guys and others laid the solid and vital foundations for the modern understanding of how Earth's climate works. They got all the basics right: it is organisations like NASA that are still filling in the important details. The more we end up knowing about how this planet works the better, especially if the USA plans to continue its exploration missions to other planetary bodies.

Atmospheric CO2 levels have now gone past 400 parts per million. That's up 40% from the pre-industrial level of 280ppm - thanks in great part to the burning of the fossil fuels. Now, as a businessman, you can understand numbers. Some folk like to downplay the importance of gases occurring at, they say, small concentrations. But we think that if we knocked on your office door with details of a whole mountain containing an average of 400ppm gold, you'd sit down and listen.

We cannot look anywhere within the geologically recent series of alternating ice-ages and interglacials to see an Earth with more than 400ppm carbon dioxide in its atmosphere. We have to go back a lot further. To see a 400ppm-plus planet, we need to time-travel to the mid-Pliocene, 3.5 million years ago. Back then, Arctic Siberia, today a barren tundra, was shrouded in boreal forest. That might sound OK, but such warmth has its price. Due to less ice at the poles, it was also a time when sea-levels were around twenty metres higher than those of today. That's not good if you have beach-front real estate. Such changes can take many years to bring about, but Earth's physical systems always move towards balance. Earth systems obey the laws of physics, not economics. They take no notice at all of electoral cycles or partisan politics. They don't care which guy you voted for.

Mr President-elect, we have to work with the Earth, not against it.

For a full account of the history of climate science, please follow the link below.

Comments

Your history makes for interesting reading, and I think your conclusions are 100% valid. However I dont think Trump really believes climate change was a scam invented by the Chinese. Trump is not quite that crazy. This was simply emotive rhetoric to get votes from his particular target audience.

Trump's positions appear to be somewhat flexible. However his appointment of hard line climate sceptics suggests that Obamas work will be at least partly scaled back. Trump may try to have climate change policy both ways to appease all interests, so he may keep some policy but quietly undermine other policies in the background. This needs to be watched carefully and exposed if it appears to be happening.

Just on a related issue of climate history, a lot of people I talk to think global warming is a good thing because it could stop the next ice age. Trump may believe this himself. My understanding is global warming cant stop an ice age or even soften one.

From what I have read is if we burned all the fossil fuels on the planet, warming would last about 5,000 years and then start to return to lower temperatures well before the next ice age, let alone the ones after that. However I'm not certain how firm the science is on this issue.

I'm just thinking that the IPCC should perhaps discuss this in its advice to policy makers, and it needs more public awareness.

No government today is going to implement any kind of policy to address the climate of the planet 5 to 20,000 years from now, and nor should they.

The issue with modern climate change is the pace at which it is occurring. Climate changing slowly over thousands of years (ice age transitions) is inevitable and something we can adapt to much more easily than rapid change over decades. It's difficult enough to get politicians to think that far ahead. Prognosticating thousands of years ahead for policy purposes is a needless distraction.

My understanding is global warming cant stop an ice age or even soften one.

That stetement is demonstrably invalid. Start by read ing e.g. Archer 2005, then his following articles in 2007, 2009 etc. Others may provide links and other copious supporting material. I have tine to only say that virtually all climate/carbon models (not just David's model) predict that moving all fossil fuel C (ca 5000Pg) into athmosphere would result in enough warming to skip the next ice age cycle. Even with the amount we've already added, the next ice age may already be disturbed, of course depending what you mean by "disturbed"

Further to chriskoz, even without human intervention, an ice age is not expected for 50,000 (see Berger & Loutre 2002). However, the ice age cycle is a Pleistocene phenomena - when natural CO2 levels got low enough for the milankovich cycle effect on albedo to come into play - and when we last had 400ppm of CO2 in Pliocene, then we didnt have ice ages. As Barry says, the issue with climate change is speed (can we adapt fast enough) and the ice age is incredibly slow compared current rates of change.

Thank's for the feedback, but I did not suggest government consider ice ages or that far ahead. I did not suggest that the current rapid rate of climate change is not an issue. By stopping an ice age it should be self evident I meant cancel the drop in temperatures, not stop the underlying cause.

I simply said that a typical sceptical argument is that global warming is good because it would stop or slow down the next ice age and indeed all ice ages. My understanding was global warming cannot even stop the next ice age as per this article below, so theres no long term benefit to global warming.

My comments were made in good faith. The article seemed quite convincing. However I accept comments that most research does strongly find that global warming could at least reduce the effects of the next ice age.

However it would be unlikely that global warming would be permanent, and would cancel all future ice ages.

"But shouldn’t Earth now, or at some point, be headed into the next ice age?No. Another ice age will not occur, unless humans go extinct. Orbital conditions now are, indeed, conducive (albeit weakly) to initiation of ice sheet growth in the Northern Hemisphere. But only a small amount of human-made GHGs are needed to overwhelm any natural tendency toward cooling. The long lifetime of human-made CO2 perturbations assures that no human generation that we can imagine will need to be concerned about global cooling.Even after fossil fuel use ceases and its effect is drained from the system an ice age could be averted by chlorofluorocarbons (CFCs) produced in a single CFC factory. It is a trivial task for humanity to avert an ice age."

nigelj - sorry if that came over too aggressively, i know you meant well. I cant moderate on a thread that I am commenting on, but can I suggest no more comment on this so that we all conform with the "no dogpiling" rule.

I would go even further: this government (i.e. president-elect) not only cannot "think that far [thousands of years] ahead", it provides plenty of evidence that it does not even think of the reality of the moment. I'm very confident that this article, if presented to president-elect, will be dimissed as unimportant distraction, or if forced to read it, president-elect would likely not even understand it. President elect made more than obvious and on many occasions, that the only "facts" he accepts as real are those that make him the "winner" in his mind, even if those "facts" are in fact falsehoods. The very recent example: in 2012 he called Ellectoral College a 'disaster', in a mistaken belief that Romney won the popular vote (he didn't) over Obama. Now, he is happy about EC because it made him win:

Since winning the 2016 election, Trump has been tweeting about the "genius" of the Electoral College system, because "it brings all states, including the smaller ones, into play."

and at the same time is criticising popular vote by inventing conspiracy theories of "millions of fraudulent votes for Hillary Clinton". He does not need to invent such theories, just accept the "genius" system, but he has to boast ego that he's always a "winner" in every game, even by inventing non-sense theories.

It becomes clear that the factual argumentaion in this article is futile if directed to a person such as president-elect. Different type of arguments (e.g. reinforcing his ego along the way) are needed. However this article is important as an open letter to be read by the supporters who elected him. I have a faith that the level of understanding/acceptance of reality by those average american voters is higher than that represented by president-elect. And they realise their mistake of electing such grossly incompetent president. The soonner they do, the better.

As the author of this piece, I'll just reply to nigelj (post #2) on the topic of ice ages.

Earth has had two climatic states over the Phanerozoic (the Age of Visible Life) that represents the last 541 million years: Hothouse and Icehouse. Both are vividly recorded through that time-span by the geological record.

In an Icehouse climate state, the climate cycles between warm and cool, or in technical terms interglacial and glacial. There are Polar ice-caps throughout, but in cool cycles, ice-sheets develop more widely.

In a Hothouse climate state, the climate cycles between warm and hot. There are no Polar ice-caps and the positions of Earth's climate belts are different to those of an Icehouse.

We are currently in a warm phase Icehouse, and would be on schedule to enter the cool phase in several thousands of years' time, but we have altered the atmosphere significantly. We are about a third of the way to taking it to a full-blown Hothouse atmosphere. Whatever point we manage to stop at on that journey, Earth will come in time to equilibrium with the properties of the atmosphere at that point. It's what natural systems do.

Trump says he has 'an open mind' about Climate Change. In the same interview, he says CC is 'a very complex subject', says on one hand 'they have science' and on the other hand 'there are those horrible [Climategate] emails... where they got caught, you know', says 'we've had storms always', and says 'the hottest day ever was in 1890-something'. Today we learn KellyAnne Conway, his campaign manager and likely press secretary, will travel to the Alberta tar sands in January, to highlight its importance to America. So, in this case, we're talking about an 'open mind' filled with Koch-propaganda.

What will Trump really bring to the Climate Change discussion? Consider that yesterday Dr Jeff Masters, founder of The Weather Underground website, appealled for donations for the Climate Science Legal Defense Fund (CSLDF), to defend U.S. Climate Scientists from a tidal wave of McCarthyist witchhunts in Congress designed to chill their research. To quote: "[Lamar] Smith’s House Science committee issued more subpoenas in his first three years than the committee had for its entire 54-year history; many of these subpoenas demanded the records and communications of [climate] scientists who published papers that Smith disapproved of."

John Mason @10, thanks but I am still mystified on a couple of points as follows.

First I want to point out I see global warming as a problem for humanity, and am on record on this website saying this.

However being devils advocate, isn't a warm / hot climate phase long term actually preferable to a warm / cold climate with periodic ice sheets over most of the northern hemisphere? Ice ages are a real killer and hard to adapt to. On that basis some might say global warming is a good thing.

And I dont see how earth would enter a permanent warm / hot phase. Wouldnt the excess atmospheric CO2 gradually be reabsorbed into the oceans? And given we have had a warm / hot climate in the distant past something caused it to change to a warm / cold system. So I just struggle to see that we would be in a permanent warm / hot system for all eternity.

We now can add a female scientist to the history of climate science as the first to prove that CO2 effectively traps the sun's heat. In 1856, she concluded on the basis of her experiment that, “An atmosphere of that gas would give to our earth a high temperature; and if as some suppose, at one period of its history the air had mixed with it a larger proportion than at present, an increased temperature [from its own action as well as from increased weight] must have necessarily resulted.” http://www.climatechangenews.com/2016/09/02/the-woman-who-identified-the-greenhouse-effect-years-before-tyndall/

Unfortunately, European scientists were unaware of her report, and she did not carry her research on the subject further.

nigelj@13 said: "So I just struggle to see that we would be in a permanent warm... system for all eternity." No. We would be in a temporary warm system just long enough to erase most of our coastal cities, which conduct the vast majority of our trade. Jim Hansen on this (15' video).

ubrew @12, yes thanks I get that. Global warming will cause serious sea level rise. We have had maps published in my country on the extent and it's not good.

I was really just asking if we continute to burn fossil fuels at current rates will this cause permanent global warming for billions of years, or temporary global waming of a few thousand years (or how much would we expect?) or dont we know?

So far I have received mostly conflicting and blunt or hostile answers.

Nigelj - this argument is sometimes put forward, although it has a major flaw. It's not the end-state but the transition from here to there that is so deadly. Sea-level rise, as pointed out above, destroys the economic infrastructure of all countries to a large or massive degree. That can't be good. However, more serious again is the shifting of Earth's climate belts with respect to their current position. That variably but inevitably takes out a) habitability and b) agriculture. We have seen the desperate situation of folk fleeing the conflict in Syria - the boats, the mass-drownings, the political instability in parts of Europe. Maybe a million people are trying to find sanctuary. Let the climate run away with itself and you're looking at hundreds of millions.

Another assumption I've seen put forward is that defrosted permafrost country in the far north will compensate for such issues - however, the timeframe is too long. Soils do not develop overnight - they are the product of thousands of years of biochemistry. Soil is a lot more complex than most people realise, yet we take it for granted in the same way we expect to find tins of beans on the supermarket shelf.

It was a lot easier for our ancient predecessors to move south or north as the Quaternary ice-sheets waxed and waned. Small bands of hunter-gatherers, with no governments or nations and borders, had a fraction of our modern problems to address. I could live off the land - and from the sea - if I needed to. I do so to an extent already. But the fraction, in the West, that have such capabilities - or even the ability to learn them and put them into practice - is tiny.

It is my understanding that the changes in heat on the Earth from current emissions will last about 100,000 years. That is not the rest of the life of the Earth, but no-one currently alive will be around to see sea level what it is today. How long is forever for you? Already the climate will not be the same as it was in 2000 until long after everyone now living has passed on. If sea level rises 25 meters (in 1000 years) it will cover all the great deltas of the world which include a very large percentage of arable land. Several billion people would be displaced with no-where to go. It was pointed out above how much disruption is caused by one million refugees, imagine 300 million from 2 meters of sea level rise. That is in the range of what is expected by 2100.

Look at the linked videos from James Hansen above. He goes into more detail.

William Ruddiman suggests that humans have been affecting climate for 7,000 years. His view has gained a lot of support in the last few years, but has not yet reached consensus. According to this hypothesis we would currently be in the start of the next ice age without human intervention.

Michael Sweet @18, fair comments. It was my understanding elevated temperatures would last about 3000 years, but I want to emphasise even that is a serious problem. Clearly it is also proceding at a rate that could be hard to adapt to. Last years temperatures would suggest the so called pause is over and that we are on track to lock in substantial sea level rise.

I have already read a long article on Ruddimans work that basically suggests farming and deforestation have caused some warming for the last 5,000 years or so and are an explanation for the unusually mild interglacial period we have experienced. It sounds distinctly plausible.

Given global warming will have a definite life span whether 3,000 or 100,000 years it cannot stop all future ice ages. I was just thinking long term that "if" global warming could permanently eradicate all ice ages it might be a good thing. Maybe this was an off the wall thought. But clearly global warming cant stop all ice ages. Ice ages are also slow phenomena so possible to adapt to one assumes.

Given global warming will have a definite life span whether 3,000 or 100,000 years it cannot stop all future ice ages [...] . Maybe this was an off the wall thought. But clearly global warming cant stop all ice ages.

No, this is false. AGW has the potential to last longer than 100Ky and definitely stop several ice ages. Despite scaddenp request not to "dogpile", I have to respond to such false statements, that you're persitently making. Looks like my response @4 was inadequate so I elaborate in detail here.

Understand the processes of Carbon uptake from this post.Visualise the timescale of these processes it by looking at a picture in this comment and/or by reading Archer 2007.Note that the slug of 4000-5000Pg of C, as David points in table 4, results in the residual over 30% of that slug (coloured red in the picture) staying in atmosphere beyond 40Ky timeframe of that picture. The "reaction with igneous rocks" (also called "rock weathering") that would eventually remove that residual has 100Ky+ up to 500Ky timeframe. That's half a million years.

Now, turn to Archer 2005 where David desrcibes the "trigger model" of the glaciation onsets, particularly Figure 3 therein. In the middle of it, you see the periodic signal of Milankovic forcing (i.e. summer insolation variations in the arctic) in -/+500Ky timeframe. According to the model, the onset of ice age happen when said signal falls below the horizontal green line (i.e. the Milankovic forcing is not strong enough to melt the accumulated snow resulting in ice accumulation around N Pole). You can eyeball that in the next 500Ky, the Earth could face potentially up to 10 ice ages (Milankovic signal crosses green horizontal line 10 times). The very first, in ca 60Ky is a weak one but the next one in ca 120Ky, and several next ones are a strong ones.Now, addition of some CO2 to the atmosphere will last up to 500Ky and result in warming in the arctics, therefore the green line triggering the glatiation will be lowered (because in warmer arctic, colder Milankovic signal is required for the ice to start accumulating). Figure 3 shows two scenarios of 1000 & 5000Pg C slug added to the atmosphere. The corresponding two red lines lower the glaciation threshold of horizontal green line. You can eyeball that the red line corresponding to 1000Pg C slug (the amount we're committed to achieve and likely surpass, even with strong AGW mitigation action) just lowers the threashold to the boundary of first predicted weak glaciation. Which means, we may have already postponed the first impeding glaciation in ca 60Ky. The second red line corresponding to 5000Pg C slug, total FF reserves that we are able to add to the atmosphere, brings said threashold beyond the variability of Milankovic forcings on the figure. Which means, that such disturbance would deprive the Earth of any glacial cycles for the next 500Ky.So, the above is the proof that your statement above is false. AGW can (and likely will with the policies boasted by the current president-elect implemented in the next 100-200y until the exhaustion of FF reserves) overturn the Pliocene glacial cycles. Homo sapiens are in charge of the Earth's climate, among other things, on such long geological timescale.

I would like to add that David, like most mainstream climate scientists, prefers to err on the conservative site: e.g. his jumper & trigger models do not include feedbacks that cannot be quantified such as permafrost melting positive feedback). Given that more positive than negative such non-quatifiable feedbacks exists, the true influence of AGW on glacial cycles may be higher than stated in Archer 2005. But that's just my speculation.

Please post further questions about ice ages in the threads I linked above, I won't respond here anymore.

The key issue wrt the degree of permanancy is ice sheet melt. Greenland and West Antactica seem to have significantly melted and refrozen over the past glacial cycles. If the impact of anthropogenic warming doesn't exceed that magnitude then we would expect that the cycles would re-establish themselves. It may be that we defer or weaken the next expected cycle but that would be about the limit.

However, if we screw up completely and produce enough CO2 to yield sufficient warming to completely thaw all of Antarctica before CO2 levels drop, then it may take much longer for ice sheet nucleation to restart there. We well could flip into a hothouse climate for a time, maybe millions of years, and reverting back to an icehoiuse climate would be slow. Eventually that would probably happen - having a continent sitting over the south pole, isolated from everything else and surrounded by a huge ocean current is a strong driver towards an icehouse climate.

Chriskoz @20, sorry if I ruffled your feathers. You wont reply so I make this comment for the benefit of others: You, John Mason, Glenn Tamblyn and Michael Sweet have all given different versions of how long elevated temperatures would last, and the implications, and I have read other versions as well myself, so its hard for me to know.

While your version is compelling you yourself acknowledge uncertainties in it.

But if global warming essentially cancels the next 5 ice ages over such an extended period does this not have an upside? Ice ages are killer events. Its a valid question.

Or are uncontrolled experiments with the planet by injecting so much CO2 just uncertain and high risk?

The main point Nigel - that most of us have mentioned - does not involve the next tens of thousands of years. Substantial sea level rise comes a lot quicker. Whatever follows that just rearranges the mess.

Just a second point in response to feedback regarding ice ages. Yes they would present problems due to ice sheets gradually spreading over northern continents over many tens of thousands of years (although many areas that would be affected are at present sparsely populated). However, there's something else to think about. Sea level fall. During the last glaciation, sea-levels fell by approximately 125 metres and remained around that lowstand for many thousands of years - long enough for the continental shelves of the world to - in part at least - become fertile plains. Look up Doggerland, as but one example - where people lived, hunted and forage and now the sea-bed of the North Sea.

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